Rare cases of recurrent life-threatening allergic reactions to red meat have been linked to tick bites, according to researchers from the National Institute of Allergy and Infectious Diseases (NIAID).

Lone Star ticks range from the Southeast through the Eastern United States and bites from the arachnids are known to cause a rare allergy to galactose-α-1,3-galactose (α-gal), a type of sugar found in beef, pork, lamb, and other red meats. Now, researchers from NIAID have found antibodies to α-gal in the blood of 6 of 70 individuals treated for recurrent, unexplained anaphylaxis. All 6 individuals had a history of tick bites and lived in states where Lone Star ticks are common. Adopting red meat-free diets allowed them to avoid further anaphylaxis for the duration of follow-up, which ranged from 18 months to 3 years.